docs: def main():
      """ Build a standalone dql executable """
      venv_dir = tempfile.mkdtemp()
      try:
          make_virtualenv(venv_dir)
  
          print("Downloading dependencies")
          pip = os.path.join(venv_dir, "bin", "pip")
          subprocess.check_call([pip, "install", "pex"])
  
          print("Building executable")
          pex = os.path.join(venv_dir, "bin", "pex")
          subprocess.check_call([pex, "dql", "-m", "dql:main", "-o", "dql"])
  
          print("dql executable written to %s" % os.path.abspath("dql"))
      finally:
          shutil.rmtree(venv_dir)